NGC 1491 SHO

[john2y]

I haven't seen many images of this nebula and I felt sorry for it so I started gathering data about a month ago. I'm done with Ha data but I'm still working on Oiii and Sii so the result is a bit noisy. This was just a test processing to see what colours I should expect. What is hard about imaging this object is that the center part the " blue arrow" is really bright but the rest od the nebula is very dim so I had to fiddle with the curves and masks a lot.

Taken with Explore Scientific 102/714 with 0,8x flattener and ASI1600MM Pro with ZWO NB filters.

Data gathered: 254x180s Ha, 31x180s Oiii, 28x180s Sii

Processed in Pixinsight

[don4l]

I captured this accidentally when I was imaging SH2-205.  I was struck by the incredible range of brightness and wondered how to process it.  My normal methods of stretching wouldn't show the whole object - so well done!

 

[john2y]

1 hour ago, don4l said:

I captured this accidentally when I was imaging SH2-205.  I was struck by the incredible range of brightness and wondered how to process it.  My normal methods of stretching wouldn't show the whole object - so well done!

 

I made a mask using rage selection tool in pixi and lowered the brightness of the center, then reverted the mask and increased the brightness of the rest of the nebulosity.

[peter shah]

like you say not one you see very often, nice capture

[john2y]

22 hours ago, peter shah said:

like you say not one you see very often, nice capture

Thank you! Hopefully it'll improve once I add more oxygen and sulphur data.

[04Stefan07]

Woah, that is a fantastic shot!

I recently purchased the same scope and happy with it. I am trying to look for a suitable focal reducer for it. May I ask which brand/model of focal reducer you are using with the 102?

Thanks!

[john2y]

15 hours ago, 04Stefan07 said:

Woah, that is a fantastic shot!

I recently purchased the same scope and happy with it. I am trying to look for a suitable focal reducer for it. May I ask which brand/model of focal reducer you are using with the 102?

Thanks!

This one https://www.altairastro.com/lightwave-0.8x-reducer.html and I'm quite happy with it ? 

[04Stefan07]

6 hours ago, john2y said:

This one https://www.altairastro.com/lightwave-0.8x-reducer.html and I'm quite happy with it ? 

Thanks!

Good price as well. Is there also a 0.63 option?

[john2y]

11 hours ago, 04Stefan07 said:

Thanks!

Good price as well. Is there also a 0.63 option?

There is 0.6x but from what I head the stars towards the edge are elongated anyway and you end up cropping a lot. 

[04Stefan07]

On 13/11/2018 at 20:20, john2y said:

There is 0.6x but from what I head the stars towards the edge are elongated anyway and you end up cropping a lot. 

Ah ha!

Bit hard to get the reducer in Australia. Found this other one but not sure if it will work or not.

https://www.bintel.com.au/product/orion-focal-reducer-0-8x-refractor/

[john2y]

9 hours ago, 04Stefan07 said:

Ah ha!

Bit hard to get the reducer in Australia. Found this other one but not sure if it will work or not.

https://www.bintel.com.au/product/orion-focal-reducer-0-8x-refractor/

I think it should work as they don't state that it's limited for some specific focal ratio so go for it. 

[04Stefan07]

18 hours ago, john2y said:

I think it should work as they don't state that it's limited for some specific focal ratio so go for it. 

Ah, found info on it and it doesn't support our focal length.

Found your one from a UK company which I can purchase from.

Altair also make a 0.6x version which I found, as you said guessing there would be too much vignetting.